/*---------------------------------------------------------------------------------------------
 *  Copyright (c) Microsoft Corporation. All rights reserved.
 *  Licensed under the MIT License. See License.txt in the project root for license information.
 *--------------------------------------------------------------------------------------------*/


import { readdirSync } from 'vs/base/node/pfs';
import { statSync, readFileSync } from 'fs';
import { join } from 'vs/base/common/path';

export function buildTelemetryMessage(appRoot: string, extensionsPath: string): string {
	// Gets all the directories inside the extension directory
	const dirs = readdirSync(extensionsPath).filter(files => {
		// This handles case where broken symbolic links can cause statSync to throw and error
		try {
			return statSync(join(extensionsPath, files)).isDirectory();
		} catch {
			return false;
		}
	});
	const telemetryJsonFolders: string[] = [];
	dirs.forEach((dir) => {
		const files = readdirSync(join(extensionsPath, dir)).filter(file => file === 'telemetry.json');
		// We know it contains a telemetry.json file so we add it to the list of folders which have one
		if (files.length === 1) {
			telemetryJsonFolders.push(dir);
		}
	});
	const mergedTelemetry = Object.create(null);
	// Simple function to merge the telemetry into one json object
	const mergeTelemetry = (contents: string, dirName: string) => {
		const telemetryData = JSON.parse(contents);
		mergedTelemetry[dirName] = telemetryData;
	};
	telemetryJsonFolders.forEach((folder) => {
		const contents = readFileSync(join(extensionsPath, folder, 'telemetry.json')).toString();
		mergeTelemetry(contents, folder);
	});
	let contents = readFileSync(join(appRoot, 'telemetry-core.json')).toString();
	mergeTelemetry(contents, 'vscode-core');
	contents = readFileSync(join(appRoot, 'telemetry-extensions.json')).toString();
	mergeTelemetry(contents, 'vscode-extensions');
	return JSON.stringify(mergedTelemetry, null, 4);
}